Copper zinc water filtration is a high-purity brass water filtration process that relies on the redox potential of dissolved oxygen in water in the presence of a zinc anode and copper cathode. It uses dissolved impurities within water as constituent substrate, which are reduced to more physiologically inert compounds. Due to inherent limitations in bactericidal and antiprotozoal activity and poor filtration of organic chemicals (in particular organophosphate pesticides), copper zinc water filters are not commonly used in the household setting unless combined with carbon based systems. They also have application in the industrial setting to extend the life of carbon based filtration systems for waste water effluent. Chemistry In the filtration process, zinc acts as an anode and copper as a cathode in an electrolytic cell. Ionic contaminants are removed by electron exchange (a redox reaction), in which they are converted to a more physiologically inert form. This redox reaction generates an electric potential of about 300mV, which may be responsible for the partial antimicrobial effect, along with hydroxyl radicals that form during the process. Specifications The process can remove chlorine, hydrogen sulfide, heavy metals, iron, and can reduce certain inorganic contaminants. The filter also inhibits the growth of algae, fungi, and bacteria to an extent. Copper zinc filtration has been used in municipal processing, and the treatment of medical and dental waste water, as well as for industrial effluents. They can be a component of whole home water filtration systems at point of entry or inline with shower heads or sink heads at point of use, as they remove many forms of dissolved chlorine and are effective at higher temperatures. One of the earlier described commercial methods for copper zinc water filtration is via kinetic degradation fluxion media (KDF), a product whose main filtration line consists of brass granules with varying proportions of zinc and copper alloy. It was developed in 1984 and patented by Don Heskett in 1987. An alternative KDF media is a matrix of fine metal similar to steel wool. Filtration and usage Amongst copper zinc water filtration methods, KDF is certified to the NSF International Standard 61 for water treatment plant applications, and the 2010 NSF standard for drinking water treatment units. A 2005 report by the US Department of Health and Human Services found that, under normal operating conditions, a treatment of contaminated groundwater in the Cedar Brook area consisting of KDF and activated